When designing integrated circuits (IC), such as mixed signal ICs, it is often desired to reduce or minimize the number of external power supplies required. However, various specified voltage levels may be required by portions of the IC, to be provided at a certain load current. Charge pumps are commonly used to generate these various voltage levels beyond what is provided by external power supplies, reducing the number of required external power supplies. However, factors such as parasitic capacitance and power dissipation across transistors may reduce charge pump efficiencies, particularly at higher clock frequencies. Thus, any improvement in charge pump efficiency is beneficial.